The present invention relates to an electrical control device for a motor-driven derailleur for bicycles.
More precisely, the invention relates to a control device of the type comprising:
a supporting body provided with means for fixing it to the handlebars of a bicycle;
a brake lever mounted on the supporting body in such a way that it can oscillate about a first axis;
a pair of electrical switches for controlling gear change, which are carried by the supporting body; and
a gear lever which can be operated manually for controlling one of said switches.
A control device of the type specified above is known from the U.S. Pat. No. 5,470,277 in the name of the present applicant, which describes an electrical control device provided with two switches set in a supporting body fixed to the handlebars of a bicycle. One first switch is operated by a gear lever set immediately behind the brake lever, and a second switch is operated by means of a push-button located on a side wall of the supporting body. The two electrical switches make it possible to actuate an electric motor associated to a derailleur for bicycles in two opposite directions. Actuation of the motor of the derailleur in one first direction makes it possible to obtain shifting of the chain in one first direction, for example towards the higher gear ratios, whilst actuation of the motor in the opposite direction corresponds to shifting of the chain in the opposite direction, for example towards the lower gear ratios.
The document U.S. Pat. No. 6,015,036 describes an electrical control device for a bicycle including a switch for controlling gear change, which is supported by the brake lever. A second switch for controlling gear change may be set in the vicinity of the brake lever. This solution is not as advantageous as the one in which both of the switches are set on the supporting body in so far as it entails the need to bring an electrical connection onto the brake lever, which oscillates with respect to the supporting body.
The purpose of the present invention is to provide a an electrical control device of an improved type which is simple from the constructional standpoint and has greater functionality than known devices.
According to the present invention the above purpose is achieved by a control device having the characteristics specified in claim 1.